Understanding Chemical Formulas and Atomicity

The video tutorial explains the concept of chemical symbols and formulas, illustrating how elements are represented by unique symbols and how subscripts indicate the number of atoms in a molecule. It provides examples like O2 for oxygen and H2O for water, showing how chemical formulas convey the composition of molecules. The tutorial also introduces atomicity, the total number of atoms in a molecule, with examples such as oxygen (O2) and sulphur (S8). It highlights that inert gases have an atomicity of 1 as they exist independently.

What does a subscript in a chemical symbol indicate?

• The number of atoms of that element

• The number of molecules

• The charge of the element

• The type of element

Which of the following is the correct chemical formula for water?

• O2H

• H2O

• HO2

• H2O2

What elements make up the chemical formula NaCl?

• Sodium and Oxygen

• Nitrogen and Chlorine

• Sodium and Chlorine

• Nitrogen and Oxygen

What does the term 'atomicity' refer to?

• The number of molecules in a compound

• The charge of a molecule

• The total number of atoms in a molecule

• The type of bonds in a molecule

What is the atomicity of an oxygen molecule?

• 3

• 2

• 1

• 4

Which element has an atomicity of 8?

• Oxygen

• Sulfur

• Phosphorus

• Nitrogen

What is the chemical formula for phosphorus as a molecule of elements?

• P2

• P3

• P4

• P5

Which of the following elements exists as N2 in nature?

• Chlorine

• Nitrogen

• Sulfur

• Oxygen

How do inert gases exist in nature?

• As molecules of elements

• Independently

• As compounds

• As ions

What is the atomicity of inert gases?

• 4

• 3

• 2

• 1